Modern hard disc drives comprise one or more rigid discs that are coated with a magnetizable medium and mounted on a spindle hub of a spindle motor for rotation at a high speed. Information is read from and written to each disc on a plurality of concentric tracks by a read/write head mounted on an actuator arm. The outside circumference of each disc is referred to as the “outer diameter” (OD), and the center of each disc is referred to as the “inner diameter” (ID). A read/write head is said to “fly” over the disc surface as the disc rotates. When disc rotational velocity decreases, the layer of air supporting the read/write head above the disc surface diminishes and the head descends toward the disc surface. Contact between the read/write head and the disc surface can damage the magnetizable medium and the head. Furthermore, through a phenomenon called “stiction,” a read/write head can become temporarily “stuck” to the disc surface after landing on the disc surface. Stiction can damage the magnetizable medium, the read/write head, and/or the actuator arm when the disc drive system initiates disc rotation in an attempt to move the read/write head from the disc surface.
A conventional contact-start-stop (CSS) solution may be used to address this problem. In a disc drive system utilizing a CSS interface, a read/write head lands and is parked on a textured landing zone, preferably near the ID of the disc, as the disc loses rotational velocity and eventually completes spinning. Typically, data is not recorded in the landing zone, and the texturing of the landing zone surface minimizes stiction. The read/write head is moved from the landing zone and back to data areas on the disc when the rotational velocity increases to allow the head to fly above the disc surface.
In order to decrease flying height and increase aerial density, conventional CSS solutions have moved toward the use of a padded slider taking off and landing in a laser textured landing zone with lower laser bumps. However, such an implementation is not without problems. For instance, the padded slider solutions result in high friction forces during contact between the slider and the landing zone. Furthermore, a padded slider may result in excessive wear of the coating on the disc. Yet another problem associated with padded sliders concerns normal wear, and thus maintenance of, the padded slider pads. Excessive wear of both the coatings on the discs and the pads on the sliders may lead to premature failure and crash of the head media interface. Wear of the slider pads may also result in an increase of stiction between the slider and the disc surface.